The ninth volume of this series offers a special feature not found in previous volumes--tutorial review papers covering such areas as acoustical microscopy, imaging in on destructive evaluation, ultrasonic imaging by reconstructive tomography, theory and measurements of ultrasonic scattering for tissue characterization, underwater acoustical imaging, and seismic imaging. In addition to these fine tutorial papers, Volume 9 takes and in-depth look at methods, transducers, processing and display, phased array considerations, transmission imaging, ultrasonic diffraction tomography, tissue characterization and impediography, and medical applications.